Method of and apparatus for utilizing mine waste by means of the heat of dump-heaps



w. osTwALD. METHOD 0F AND APPARATUS FOR UTILIZING MINE WASTE BY MEANS 0FTHE HEAT 0F DUMP HEPS APPLICATION FILED JULY 2l, I9I6.

Patented Feb. 22, 1921.

` App -UNTTED STATES PATENT OFFICE.

WALTER OsTWALD, OE GROssROTHEN, SAXONY, GERMANY, AssIGNoR,` :mrfiznasiwnASSTGNMENTS, To THE CHEMICAL FOUNDATION, `No., A CORPORATION OE DELA-WARE.

METHOD OE AND APPARATUS FOR UTTLIZING MINE WASTE EY'MEANS OP THE HEAT vOE DUMP-HEAPS.

Applcation'led July 21, 1916. Serial No. 110,619.

T o all whom t may concern:

Be it known that I, WALTER OsTWALD, a resident of Grossbothen, Germany,and citizen of Saxony, have invented certain new and useful Improvementsin Methods of and aratus for Utilizing Mine Waste by Means of the Heat fofY Dump-Heaps, of which the following is a specification.

This invention has reference tothe utilization of mine waste, that -isto say, oirub-y `i bish resulting from miningand like operations, suchas the heaps of rubbish mainly found in eollieries, heaps of oilyshale,or any otherrubbish heaps of suitable waste. Such heaps whichaccumulate very rapidly during: the process of washing coal or otherpreliminary treatment always contain very; considerable amounts ofcarbon.` Being very closely packed together and vfrequently penetratedby a goed deal quently become heated and self-ignite with the resultthat they increase in bulk, begin to smoke and make the wholeneighborhood smoky. VNo external heat is usually necessary `to startcombustion; in some cases,

however, on account of the great amount of water poured on the heaps,self-ignition does not Occur, `and it willbe necessary to startcombustion by means of a flame. As soon as combustion has started itbecomes unnecessary to supply external heat, as the heap will burn outby itself. y

- Now the present invention has for object toY prevent the heat frombeing wasted and the gases and vapors evolved from injuriouslyfaffectingthe vicinity and alsoA tov` enable the metals or metalloids andespecially nitrogen contained in the wastematerial, to be recovered aslchlorin compounds,in the form of vapors` the concentration andpurification of which-canbe effected in one and the same Operation, bymeans of the heat derived from combustion of the Waste.

Now the principal feature of the present invention consists in thefactthat, for the purpose of obtaining non-metals, vsuch as nitrogen,and metals, such as zinc, in the form of chlorids,ychlorin compounds aresupplied to the mine'waste under treatment.

' Bv means of the present invention it is possible to recover upto 80percent. ofthe of moisture they'fre- Specification of Letters Patent.Patented Feb. 22, 1921.

nitrogen compounds, contained in the waste product, this being moreovereffected by the use'of the waste material itself, which by .reason ofits poor qualities as a fuel has so far been regarded as a useless andmostly even'as an injurious waste, although containing from 1.8 to 2 percent. ofcombined nltrogen. i f

By liberally introducing chlorid solution the temperature ofV combustionofthe heap may be kept low and the yield therebyl in'- creased, ywhilethe metals, and especially the metalloids, are brought into a `formwhich is more convenient for the process of purification. I It is, forinstance, advisable to recover the .combined nitrogen in the form ofammonium chlorid by the process of sublimation. among thenitrogenVcompounds which come into consideration, ammonium chlorid has theparticular property ofv passing `from The chlorids such as calciumchlorid used as reagents in the process may be obtained at small cost.:Also the presence of deliquescent salts acts favorably uponthe process.

In the carrying vout of the invention, sevf eral'pipes Vareadvantageously introduced into the heap, working at the same timethatpart of the heap which is interposed between thepipes, until said Vparthas given olf itsv valuable contents.` The air, steam or water, andchlorid vsolution required for 'the foperation are introduced into oneof the pipes, andthe products of evaporation are carried 'olf by theother of the pipes.

Figures 1 and 1L show in plan and elevation respectively an arrangementfor carrying out the present invention in 4connection witha heap ofwaste; Fig. 2 shows a double pipe for the same purpose; and-Figs. 3 and4- illustrate cooling arrangements for keeping down the temperature,which arrangements may simultaneouslybey used for the generation ofsteam. I

The waste heap a has Vintroduced into it at deinite distances apart,pipes b andY c,

' leading to perpendicular pipes cl and eV respectively. The pipes d ande are connected with the main conduits z' and f by means ofV the valvesg Vand i. The sodium or otherclilorid solution adapted to converti Vthenitrogen constituents into ammonium chlorid is introduced through thepipesV b, z' and l and the resulting gas is carried -ofl' through thepipes o, e and f, Itis ad-V vantageous'to change the direction offlow..` from time` to time in order to circumventV any kind ofobstruction which may take place in the part oi. the heap between the Ypipes b and c. In this manner it is possible vandithrough` the otherpipe the evaporation Yproductsare carried oil. In this case also it isadvisable from' time to timeV to reverse the flow.

Besides these pipes which serve for the iny trodu'ction of air and steamand forcarry-V ing ol'gthe gases and their luy-products, it is advisableto embed special coolingV elements' into the particular zone undertreatment at they time, in order to keep down the tempera'- ture and toavoid the productionof slag.V A simple yarrangement for this purposecomprises one or more lower boilers united with an upper boiler, thelowerboilers'being set" Y `in the interior, and the upper boiler uponthe surface of the waste field. It is however Y more advantageous todivide the Ylower boiler as shown in Figs. 3 and 4:, into a 1 number ofpipes, in order to obtain greater uniformityiii the utilization"l of theheat. At the burnt-outparts of the waste field the pipes are pulled outand are again yinserted at places wherenew waste materialhas beendeposited. The pipes may be arranged as shown in Fig. 3; thc cool waterbeing introduced at o and the heated water carried off at p; whilebetween-those points there are arrangedthe conduit pipes Q, which passthrough the waste field; r and s are Vthe valves for closingthe severalconduit pipes,

' t are the severalvrotary conveying pumps for regulatingthe velocity ofHow through the pipes according to the temperature of thel various partsof the waste field being treated n by therespective `conduit pipes.V fInthe arrangement illustrated in F ig.' 4 the pipes do not "passcompletely through .the waste field but return towardthe saine side. In-

stead of the'return tubes gl there may advantageously be employedyconcentric tubes Q11, of known construction, which may more easily beintroduced into the waste heap.

lVhile the inventionis mainly. designedL for the recovery of the zincand nitrogen present in the waste, it will be understood that the methoddescribed is applicable to vthe recovery of other substances thatcan besimilarly converted into chlorids and then subjected to sublimation ordistillation.

That I claim is:

' l. The method for the utilization of mine waste by means Vofheat'derived from the' burning of said waste, which comprises add'- ingchlorin-contai'ning compounds to the waste, liberating through theutilization of said heat metals'and metalloidsf inthe form` of chlorids,and recovering the same by condensation. .Y

2. The method `forthe utilizatio of mine waste by means of heat derivedfrom theY burning of said waste,.which comprises addingchloriii-containing compounds kin con-v j unction'with water to thewaste, liberating.

throughth'e utilization of said heat metals,v

and metalloids in the form of chlorids, and recovering the same bycondensation.

3. The method for the utilization of mine waste by meansof helatpderivedfrom the burning of saidfwaste, which comprises addingchlorin-containing compounds in conjunction with water in the form ofsteam to the waste, liberating through the utilization l ofnsaid heatmetals and metalloids in the form of chlorids, and recovering the sameby condensation. n Y i g Y 4. The method for the utilization of mineburning of said waste', which comprises addeing water. containingchlorids to .the'waste, liberating through the utilization .of said heatmetals and metalloids in the :form of chlorids, and recoveringrthe samecondensation.

., The method forum iniziata 'Ofmiiie wastebymeans of heatV derivedfroid-the burning of said. waste, which Vcomprises add- VwasteV lbyvmeans .of heat derived from the f ing `deliquescent x chlorincontaining com- .l

pounds to the waste, liberating through the utilization of saidheatmetals and metalloids ien-the form of chlorids, and recoveringtliesame by condensation.

6.An apparatus for .theiutilization ,of r

mine wasteby the action of heat, comprising ing elements embedded in theglowing waste. 7. An apparatus for Y the utilization lof mine waste bythe action of heat, which com-Y prises two sets of parallel tubes incombination with :a plurality fof cooling elements,

said cooling elements beingsub-divided into a. number of tubeslconnected in parallel,

valves in each offsaid tubes, and pumps con# f' V.nected with saidtubes, iV l Y i250 two sets of parallel tubes andseparate coolj 8. Inan' apparatus for the utilization of signed my name in the presence oftwo sub- Infine Waste by the actiolrli of heat, a plirllit'y scribingwitnesses. o Cooling elements W- ich are subivi ed into a number oftubes connected in parallel, WALTER OSTWALD' valves in each of saidtubes, and pumps Vcon- Witnesses: nested with said tubes. Y 4 f RUDOLPHFRICKE,

In testimony whereof I have hereunto MUENTER RUERLER.

